Definitions for ideal gas

This page provides all possible meanings and translations of the word ideal gas

Princeton's WordNetRate this definition:(0.00 / 0 votes)

ideal gas, perfect gas(noun)

a hypothetical gas with molecules of negligible size that exert no intermolecular forces

WiktionaryRate this definition:(0.00 / 0 votes)

ideal gas(Noun)

a hypothetical gas, whose molecules exhibit no interaction, and undergo elastic collision with each other and with the walls of the container

FreebaseRate this definition:(0.00 / 0 votes)

Ideal gas

An ideal gas is a theoretical gas composed of a set of randomly moving, non-interacting point particles. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is amenable to analysis under statistical mechanics.
At normal conditions such as standard temperature and pressure, most real gases behave qualitatively like an ideal gas. Many gases such as nitrogen, oxygen, hydrogen, noble gases, and some heavier gases like carbon dioxide can be treated like ideal gases within reasonable tolerances. Generally, a gas behaves more like an ideal gas at higher temperature and lower pressure, as the work which is against intermolecular forces becomes less significant compared with the particles' kinetic energy, and the size of the molecules becomes less significant compared to the empty space between them.
The ideal gas model tends to fail at lower temperatures or higher pressures, when intermolecular forces and molecular size become important. It also fails for most heavy gases, such as many refrigerants, and for gases with strong intermolecular forces, notably water vapor. At some point of low temperature and high pressure, real gases undergo a phase transition, such as to a liquid or a solid. The model of an ideal gas, however, does not describe or allow phase transitions. These must be modeled by more complex equations of state.